1981 GS650GL Bad compression results

[Guest]

if you edit your post, click 'go advanced'.
That gives you the option to rename the title.

Thanks, renamed it to rough idle because that is what the issue is.

As for the bike: it is now a little choke reliant, like my old GS450E, maybe even more so. The idle it has when warmed up is still off to me, seems like some cilinders aren't pulling their weight.

Checked the ignition circuitry today, since I didn't really go through that last time. Primary coil windings are +-5 ohms (little less), secondary windings both floated around 25 k ohms. Pickup sensor(s) had a nice 325 ohms going for them. Battery under load dipped to 11.8V, so it was time to put it on the charger again. Perhaps the charging circuit is bad? Could that cause problems when the bike is warmed up?

The plugs in all likelihood still get gunked up, but as before it doesn't burn that much oil anymore, since it is chilling on its centerstand now. I'd really like to solve the issue once and for all, but it would be great if someone with more experience could assist with the fuel delivery system. My past experiences with that... in combination with a 2 stroke... were not too good, never got it perfect.

As for the new bike, I am sorry to inform GSresources that it is a Yamaha XJ900F from 1987. The GS850G was in a little rough shape, lots of small leaks and also running not quite right. Since I can't even make the GS650GL proper in my spare time I wasn't really too happy to try that with my daily driver.

@Steve: the first definition is quite fitting, replace ass with GS650GL and you got my meaning . Thank god it behaves normally on the highway and sorts, only with the recreational driving is the rough idle is an issue.

 

[tom203]

Progress is always nice...

"Battery under load dipped to 11.8V, so it was time to put it on the charger again. Perhaps the charging circuit is bad? Could that cause"

Fix your charging system..the ignitor might misfire if voltage feeding it gets low while running.

As for yamaha..folks here have lots of different bikes, so no problem! No sense buying a beat up suzuki when better stuff can be had.

 

[hillsy]

I've had a few XJ900's in my time and they are terrific bikes. Very underrated compared to the other big bikes of the day and the motors are bulletproof.

They were also a one year only release in the US so quite a few people here will be envious of you.

 

[Guest]

In case anyone in the future happens to find this thread: most of the problems have gone away. Perhaps an easy fix in hindsight, but after changing the oil and oil filter the motorcycle has been running a lot cleaner (read: no burning oil, no rough idle issues). Just because you don't drive a lot doesn't mean the oil stays good, or so I have heard. Other than cleaning it, new air filter, synching the carburettors, fresh oil and the valve adjustment nothing big has happened to it. So do your regular maintenance!

I don't drive it as much as I should, my XJ serves me well with the 3 piece storage on the back and fairing to keep me from getting blasted on the highway. But every now and then we spin it up and go for a ride together and it, the GS650GL, has never let us down.

 

[Guest]

The GS650GL is still going strong! After installing a new battery all of the electrical issues have gone away, perhaps it is masking the poor charging circuit... but I digress, it is doing well. As long as it keeps being reliable up to ~300KM of travel it is doing its job.

In the mean time a lot of things have changed in the garage. My trusty old XJ900F has become my father's first motorcycle and I have given myself a nice XJ550 Seca from 1981 and a Ducati Monster 900ie from 2001. The desmodromic valves on the Duc are very interesting and it drives like a treat. Both bikes are a lot of fun, in their own way. But, the GS's have always had a special place in my heart since I had the GS450E.

A few weeks ago I have decided to give in and get the bike I have always wanted: a GS850GN from 1979. It's a puzzle, literally. Bought it with an engine in a frame and two wheels attached along with a lot of parts in a few crates. Visually the bike is in a pretty darn good state for its age, with a lowish mileage of only 35000KM on the odometer. The most likely reason it has been parted is probably the destruction of its stator with nice black and crunchy wires coming from it. And yes, there is considerable resistance measurable between the three soot turned wires. I've done myself a favour and got me a new used wire loom (cable tree?). In due time I'll open another topic for it, for now I am busy removing the last pieces from the bike and breaking everything into small pieces so that I can inspect all the important bits to make it run again.

Points ignition, kickstart, 270+KGs of iron and aluminium hunks... I'm excited